Actually, I already had built my 355 for another '85 IROC that the cops made me get rid of because I had no room to restore it other than out on my driveway. I had the 355 in my '68 Corvette for awhile and then when I got my '86 IROC, I pulled the sick 305 out of it, slapped the TPI on the carbed 355 I had out of the Vette, and stuck that in the IROC. Very easy change, and I'm seeing a remarkable improvement in gas mileage.

In the Vette, I was averaging 16.5 mpg on 3.36 gears and a 1:1 final drive. In the IROC, I get 22 mpg on 3.42 gears on a 700R4. I know part of that is the improved overdrive gearing, but I'm convinced part of that is also because of the fuel injection.
Anyhow, with today's gas prices, it makes sense. 22 mpg actually makes it not too bad economically, even with expensive gas.

My suggestion would be to buy a used TPI at a swap meet, along with the harness if possible. I've seen $600 to $800 prices for those. Still a bargain compared to buying a new aftermarket EFI system. And for the street, the torque of a tuned port is a very good system. Sure, for racing, you could do better, but very few systems out there will match the torque of a tuned port, which is more important on the street.

 

Oops...this was supposed to be a response to another thread.
I hit the post button instead of reply.
Moderator, if you want to delete it, it's okay. Sorry.